The present invention relates to a method of discharging a processing apparatus for providing a predetermined process to an object to be processed, for example, a liquid crystal display (LCD) substrate or a semiconductor wafer, and to a processing apparatus having a discharging function.
In the manufacture of, for example, an LCD and a semiconductor device, a circuit is formed by the so-called lithography in which a substrate as a processing object is coated with photoresist, photoresist is exposed in accordance with a circuit pattern, and the resultant is developed.
Such a resist coating and developing process is performed by a resist coating and developing system having a cleaning unit for cleaning the substrate, an adhesion unit for providing an adhesion process to the substrate, a coating unit for resist coating on the substrate, a heating unit for heating the substrate, a cooling unit for cooling the heated substrate to ordinary temperatures, and a developing unit for providing a developing process to the exposed substrate.
In such a resist coating and developing system, a substrate mounting base and a vacuum chuck, etc., are present in each unit. The substrate is transferred to each unit by a transfer arm. However, the substrate mounting base, the vacuum chuck, and the transfer arm are easily charged, and static electricity is easily generated. Then, particles are easily absorbed on the portion where static electricity is generated. The generated particles have an adverse influence on the substrate. Moreover, this may cause breakage of static electricity. To solve these problems, an ionizer is conventionally used to discharge the portion where static electricity is generated.
However, the ionizer is a large-sized and expensive apparatus, and its maintenance is required. Also, since an attaching location of the ionizer is limited, there occurs a portion that cannot be discharged. Moreover, the ionizer itself may generate particles.